.~ One a distillation under positive pressure or vacuum {4}
78
.~.~ And returning distillation product to a previous distillation zone
DEFINITION
Classification: 203/78
(under subclass 73) Processes in which a product from a later distillation operation is returned in term of the process to a distillation zone prior to the distillation zone in which the product was produced.
SEE OR SEARCH CLASS
196, Mineral Oils: Apparatus,
99, for mineral oil distilling apparatus including the combination of a vaporizer, condensing means with means for returning a part or all of the condensate to the vaporizer.
208, Mineral Oils: Processes and Products,
355, for a process of subjecting mineral oil to at least two distillation operations in which either vapors, condensate, and/or residue from a later distillation zone is returned to an earlier distillation zone.
